This invention relates to the field of an inside-the-pipe blowout preventer.
My copending application for a "Drilling Tool", Ser. No. 201,878, discloses a full bore pressure responsive rotatable ball valve inside blowout preventer to automatically control well blowouts in the bore of the drill string. That invention significantly enhances the safety of the drilling crew and equipment from the dangers of a well blowout, but lacked a suitable sealing arrangement to prevent leakage of fluid from the bore of the tool into the well annulus when the valve operated. The longitudinal movement of the ball member of that invention needed to effect rotation of the ball required the application of large urging forces resulting in greater metal wear and a shorter reliable operating tool life.
An object of the present invention is to provide a new and improved inside blowout preventer drilling tool.
A further object of the present invention is to provide a new and improved pressure responsive inside blowout preventer drilling tool.
Yet another object of the present invention is to provide a new and improved inside blowout preventer drilling tool which may be stabbed in a drill string having a blowout flow therethrough.